Friction shock-absorbing mechanism



Feb. 8 1927. l 1,616,757

J. F. OCONNOR FRIGTION SHOCK ABSORBING MECIPINISIVI4 Filed oct. 12', 1925 2 sheets-sheet 2 Z4 Iig i {5l/ /f/ if W/ Patented Feb. 8, 1927.

@UNITED/STATES PATENT OFFICE. N

JOHN nsocoNNon, or CHICAGO, ILLINOIS, AssIGNoR, BY' MESNE v.ttssreflaiztnN'rs. To y W. H MNER, INC., A CORPORATION or DELAWARE,

FRICTION SHOCK-A BSQBBING MECIEIANISM.l

Application ala october 12, 1923. serial No. 668,056.

This invention relates to improvements in frlction shock absorbing mechanisms. `One object lof the invention is to provide a friction shock absorbing mechanism, especially adapted for yrailway draft riggings,

wherein are .obtained hi h resistance, yeasy and graduated action, an certain release by means of relatively few parts all of economic construction. v i

I More specifically, the object of my invention is to provide in a mechanism of the character indicated and of that type employing blunt and keen anglesl for effecting the i application No.- 610,198, Afiled January 2,

'15123, for improvements in=friction shock absorbing mechanisms and to which reference may be had for a more complete description of the general operation of. a mechanism e employing blunt and keen an le wedge faces similar to those disclosed in t is application. In the drawings formin a part of this specification, Figure 1 is aorizontal longitudinal sectional view of a portion of a railway draft rigging showing my improvement inconnection therewith, the section of the shock absorbing mechanism proper corresponding to two intersecting planes at 120"4 l apart, .as indicated by the section lines 1-2 of Figure 2. Figure 2 is an end elevation of the shock absorbing'mechanism proper. Figure 3 is a view similar to Figure 1 of the shock absorbing mechanism proper, the section corresponding, however, to the two yintersecting planes Indicated by the lines 2-3 of Figure 2. Figure 4 is an end elevation of the pressure transmitting wedge employed in my construction. F1 ure 5 is a view similarto Figure 3 illustrating a modified form of the improvement. And Figure '6 is a vertical transverse section corresponding tothe line 6-6 of Figure 5. l Referrin first to the construction illustrated in Figures 1 to 4, inclusive, 10-10 indicate the usual car draft sillsv to the inner the ront follower shockI absorbing mechanism proper by a hooded cast yoke 13 within which is disposed said mechanism and front and rear followers 14 and 15. The yoke and arts there- .within are supported in operative position by a detachable saddle plate 16. The mechanism is of that character employing a substantially cylindrical shell and in order to maintain it in central position I preferably employ guide plates 17-17 secured to the inner faces of the draft sills, as indicated in Figure 1.

The improved mechanism comprises, broadly, a combined friction shell and spring cage casting A; a spring resistance comprised of an outer coil B and an inner coil C; a pressure transmitting wedge D; two blunt angle friction shoes E-E; a .keenangle friction shoe F; two spring followers G and H; and a retainer bolt J.

The ca'stin A, as heretofore mentioned,

is of substantlally cylindrical form throughout and has a friction shell proper 18 formed at its front or outer end with the spring cage proper 19 rearwardly thereof. An integral transverse `rear wall 20 is provided,

the same bearing upon the rear follower 15. The interior of the shell 1 8Uis preferably formed with three, uniformly spaced, independent, cylindric friction surfaces 21,. said surfaces being converged inwardlyl of the shell and so arranged that at their inner ends they merge to form a true cylinder;

The two friction shoes E are of like construction and each has an outer longitudinally extending cylindric friction surface 22 co-o erable with one of the corresponding she l surfaces 21. On its inner side, each shoe E isprovided with an enlargement 23, the front of which is beveled or inclined, as indicated at 24, to providev a wedgeface extending at a blunt angle with respect to. the axis of the mechanism and the lines of applied force. The shoe F is similar to the shoes E except that it is provided with a much keener wedge face 25.

The pressure transmitting wedge D is formed," at its frontI or outer end with a heav flanged section- 26'which bears against 14. vThat portion of the flange 26 which is opposite the adjacent end of the keen angle shoe F is made thicker, as indicated at 26a best in Figure 3, where it will be noted that aimuch4 lesser clearance is left between saidflange and the shoe F than between the main portion of the fiange 26 and the ends of the shoesE. Inwardly of the fianged section the wedge D is provided with three wedge faces 124-124 and 125 extending at the same angles as, and cooperable With, the blunt wedge faces 24 of the two shoes E and the keen angle wedge face 25 of the shoe F, respectively. At its inner end, the wedge D is formed with an extension 27 having a. flat inner end 28 which bears against the spring follower H., it being observed that the latter is spaced from the enlargements 23 of all shoes when the parts are in full release, as shown in Figure 1. Said spring follower H is erigaged by the inner coil C only. The othery spring follower G engages the inner ends of the friction shoes on one side and the -adjacent end of 4the outer heavy coil B on the other lside.l

The operation of the mechanism is as follows, assuming a buff action. As the drawbar 12 and follower 14 move toward the right, as viewed in Figure 1, the Wedge D will be moved in unison therewith. An initial wedging action is set up between the keen'angle Wedge faces 25 and 125, and there will be a corresponding reaction exerted from the `shoes E to the wedge D. As the pressure is continued on the wedge D, the latter will move longitudinally with refer*` ence to the shoe F, thus increasing the wedging action until the point is reached where the section 26a of the wedge flange engafres the outer end of the keen angle shoe Thereafter, further relativelongitudinal movement between the wedge and shoe F is prevented and the maximum spreading action thereby determined. During the movement of the wedge and friction shoes, due to the converged friction surfaces of the shell, a differential action will'take place which is accommodated on' theblunt angle sets of faces 24 and 124.A The angles of the faces 24 and 124 will preferably be made such that there will befno appreciable wedging action on said vfaces during the compression stroke-that is to say, said faces 24 andv 124 will be of a substantially nonwedge-acting character with respect tol forces `applied parallel to the center line of the mechanism, for reasons more fully stated in my co-pending application No. 610,198.

In actual practice, I prefer that the spring follower `-Gr do not engage the inner end of the keen angle shoel F, which condition isbest illustrated by Figure 3, but the shoe v'F will be afforded suicient resistance to insure the setting u ofthe Wedge action by reason `of the resistance afforded by the disengage itself from between the shoes, or

atleast sufficiently to effect collapse of the friction unit, this collapse being induced lboth by the spring coil C and by the laterally inwardly -and radially directed forces that will have been stored up in the friction shell during the compression stroke.

lrVith the construction above described, it is evident that'the amount of relative longitudinal movement between the wedge D and keen angle wedging shoe F can be limited as desired and thereby' the maximum stresses set up in the vshell kept within predetermined limits. The improved mechanism embodies all the advantages of the broader invention of the keen and blunt angle wedge faces more fully described in my said ap plication No. 610,198 to which reference may be had for a more detailed description.

Referring next to the construction illustrated in Figures 5 and 6, A indicates the friction shell which is similar in construction to the shell shown in the preceding figures. The two blunt angle friction shoes are indicated at E-E and the keen angle shoe at F. A'corresponding pressure transmitting Wedge D' is employed, the latter having wedge faces co-operable with the rcspective wedge faces of the blunt and keen angle shoes.

In the modification shown in Figures 5 and 6, the wedge D' is provided at its inner end with a laterally extending lug 40 which enters a corresponding recess 41 provided in the keen angle shoe F and by which the two parts are interlocked with provision for a predetermined amount of relative longitudinal movement of the wedge D inwardly with respect to the shoe F. In this form of the invention also, both coils of the spring resistance B. bear upon a single spring follower G which is engaged with the inner ends of the two blunt angle shoes F/-F/- The operation will be the samel as that above described in connection with the first enlbodinient of the invention. it being evident that the keen angle shoe F will be restored to its normal position during the release action by the wedge D through the lug. 40.

Although I have herein shown and de'- scribed what I now consider the preferred manner of carrying out my invention, the same is merely illustrative and I contemplate all vchanges and modifications that lll) come within the scope `of the claims app pended hereto.

. spect to the line of applied force; pressure transmitting wedging means having inclined faces corresponding to and co-operable with lthe inclined faces of the shoesI and means cooperating with said keen angle shoe only for limiting Vthe 4relative longitudinal shiftingbetween said wedging means and said last named shoe. v

2. In a friction shock absorbinglmeclia` nism, the combination with a friction shell having interior friction surfaces converged inwardl of the shell vof a -spring resistance;

- a plurality of friction shoes co-operable with the shell friction surfaces, said shoes being provided on their inner sides with faces inclined relative to the axis' of the shell and the inclined face of'at least onevshoeextending at a more acute angle than the inclined face of another shoe;'wedge pressure transmitting means having correspondingly inclined faces engaging and co-operable with said innerinclined faces l'of the shoes; and means limitin to a predetermined amount the relativel ongitudinal' shifting between said wedge pressure transmitting means and that shoev having the more acutely inclined face, -said limiting means co-operating with said keen shoe only. i

3. In a friction shock absorbing mechanism, the combination with a shell; of a spring resistance; friction shoes slidable within .said shell; a movable wedge acting between the shoes, said shoes having inner faces inclined one to the other at an angle from within which the wedge is readily re-v leasable upon discontinuance of the actuating compression force, the inner face of one vof said shoes being at an acute angle to crev ate high frictional 'capacity in the mecha- CII nism and of such an acute angle per se that 'the initial collapse'of the shoe .and'wedge must necessarily occur' on other faces; and means co-'operating onl withsaid shoe having said acute angle a'ce for limiting the relative longitudinal movement between said wedge and lastnamedshoe.

4. In a friction shock absorbing mechanism, the combination with a friction member provided with longitudinally extending friction surfaces; of a's ringv resistance; friction elements having a so longitudinally extending friction surfaces co-operable with the friction surfaces Aof said member, one element having a face inclined at4 a-keen wedge angle relative to the axis of said member and another member having a face inclined at a relatively blunt releasing anglel relative to the'axis of said. member.; a o n'epiece member having inclined faces co-acting directly with said inclined faces of said elements; -and co-operating shoulders on said v member and element having an inclined face 'at akeen wedge angle to-limit, to a predetermined amount, the" relative longitudinal movement between said lmember and'A last named shoe only.

5. In a friction shock absorbing mechanism, the combination with a friction shell having interior, independent, cylindric friction surfaces converged inwardly -of the shell; of a spring resistance; afriction shoe co-operable with each of said cylindric friotion surfaces of the shell, all of said shoes' having inner faces inclined lto the axis of the shell and one of said faces extending at aii"icute wedging angle and remaining faces extending at ,a relatively blunt releasing angle with respect thereto; a pressure transmitting wedge having inclined faces co-operable with the respective inclined faces of said shoes; and means zo-operating only with said shoe having the keen angle face for limiting the relative longitudinal movement between said shoe having the keen angle face and said wedge.

6. In a friction shock absorbing mecha-v nism, the combination with a friction-shell having interior, independent, cylindric friction surfaces converged inwardly of the shell; of a spring resistance; a friction shoe cooperablewith each of said cylindric friction surfaces of the shell, all of said shoes having inner faces inclined to the axis ofv the shell and one of said faces extending at an acute wedging angle and the remaining faces extending at a relatively blunt non wedge-acting angle with res ect thereto; a

pressure transmitting wedge aving inclined faces co-operable with the respective inclined faces of said shoes; and means co-operating 4only 'with said shoe .havingthe keen angle'` face for limiting the relative longitudinal movement between said shoe having the keen angle face and said wedge, said means including a lateral projection on'said wedge co-operable with a corresponding adjacent shoulder ori said shoe.

7. In a friction shock absorbing mecha-v' nism, the combination with a friction shell having interior, independent, cylindric friction surfaces converged inwardly of the shell;

of a spring resistance; a friction shoe cooperab e with each of said cylindric friction surfaces of the shell, all of said shoes having inner faces inclined tothe axis of the shell and one ofI saidy faces extending at an acute Wedging angle and the remaining faces extendmg at a blunt non Wedge acting angle with respect thereto; a pressure transmitting Wedge having inclined -faces co-operable With the respective inclined faces of said shoes; and means co-operating only with said shoe having the keen angle face for limiting l the relative longitudinal movement between said shoe having the keen angle face and said Wedge, said means including a laterally 10 extending flange on the Wedge disposed opposite and adapted yto engage the outer end of said shoe.

Inllwitness that I claim the foregoing I have hereunto subscribed my name this 10th 15 day of October 1923.

JOHN F. o"ooNNoR. 

